Snowfall had been consistent for the 5 day period prior to the date of the avalanche fatality. Snowfall had been accumulating over an ice crust and due to decreasing temperatures thoughout the week the density of the snow was decreasing as well. A storm on the evening of February 25th deposited 3-4 inches of slightly heavier snow over the light surface snow of the previous storm. Moderate west winds were associated with the strom and wind-loading occurred on north and east aspects. During our snowpack investigations on February 26th we witnessed natural avalanches on north and east aspects in snow that fell with no wind influence. Without being able to gain the ridge that day we assumed that wind-loaded areas would be hgihly unstable also. We were able to observe a windward aspect where the wind had scoured the new snow and it was highly unstable as well. On the day of the accident the snow had been able to settle for a 48 hour period but colder weather allowed the weak snow structure to persist.

AVALANCHE

The victim approached a steep, wind-loaded NW aspect from above on his snowmobile. Visibility may have been poor and he was unaware of the steep terrain below. As the terrain steepened he realized that he was approaching a dangerous slope and he stopped and put his snowmobile in reverse. At this point he was at the apex of a convex terrain feature and the force of backing up triggered the avalanche. He and the snowmobile traveled down the steepening slope through trees and over rocks.

The avalanche was classified as SS-AM-D2-R3-S. Crown depth was 12-18”, width 500 feet, and vertical fall was 400 feet. Average slope angle of the start zone was 40 degrees.

RESCUE

The victim's step-son rode out for help after the accident. Neither were wearing transceivers. He found a party of snowmobilers and asked them for help. They went back to the accident site and found the victims's snowmobile since a ski was protruding fro the snow. They found the victim buried underneath the snowmobile. After checking his vitals they confirmed that he was dead. They elected to ride out and notify Search and Rescue. Search and Rescue recovered the body the next day.

Rescuers believe a Colbert man killed in an avalanche Friday afternoon while snowmobiling with his teenage stepson lost his way or was disoriented when he rode off a nearly vertical slope that immediately gave way beneath him.

William Robert Smith, 43, had been riding with his 16-year-old stepson in the popular Trapper Creek drainage north of Priest Lake around 1 p.m. on Friday. After the slide buried his stepfather, the boy, who is from Spokane, found a safe way down and went for help, said Mike Nielsen, commander of the nonprofit Priest Lake Search and Rescue Team. A group of six snowmobilers riding nearby returned with the boy to the slide site, Nielsen said.

“Our best riders would not have dropped off that high ridge route,” said Nielsen, whose rescue team recovered the body Saturday morning. The team works under the jurisdiction of the Bonner County Sheriff’s Office, which confirmed Smith’s identity. “If he was familiar with it, it was not the place you would have normally gone.”

The rescuers saw a snowmobile ski protruding from the snow and used avalanche probes to find Smith’s body buried in three to five feet of snow, his snowmobile on top of him. They found the man’s body around 3 p.m., Nielsen said. Neither the boy nor his stepfather was wearing an avalanche transceiver, he said.

The rescuers dug Smith out and checked for a pulse, but found none. The group returned with the boy to the Priest Lake resort where they all happened to be staying, and the resort’s owner contacted Nielsen.

The boy told the rescuers his stepfather had started out on the slope, then stopped and tried to put his machine in reverse, but was too late. The entire slope gave way underneath him.

The slide cut loose on a north-facing slope, starting at approximately 5,400 vertical feet and ending at about 5,055 feet, Nielsen said. The slide was about 250 yards wide by 250 yards long, he said.

The U.S. Forest Service’s Idaho Panhandle Avalanche Center issued an advisory Friday saying avalanche danger was “considerable” on north and east facing slopes above 4,500 feet, said Kevin Davis, the center’s director.

Nielsen said there are three routes into the area where the pair was riding Friday – two on the valley floor and one on the high ridge where the man went off.

“He possibly got confused,” Nielsen said. “It’s just clearly not a regular route. For whatever reason, he went down a near-vertical cliff, well in excess of 45 degrees.”